Fastening device



Sept. 16, 1941. R. W. EDWARDS FASTENING DEVICE Filed May 2, 1941Rusa-ELL N Eau/Anas INVENTOR. BY lqTTOE/VY Patented Sept. 16, 1941UNITED sTATEs PATENT oFElcE FASTENING DEVICE Russell W. Edwards, LosAngeles, Calif.

Application May 2, 1941, Serial No. 391,559

9 Claims.

This invention relates to fastening devices and has to do moreespecially with removable rivets and the like.

In the fabrication of riveted sheet metal structures-particularlyaircraft-it is the practice, as a preliminary to the riveting operation,to hold together the parts to be joined by means of fasteners in thenature of removable or temporary rivets which can be inserted quicklyand removed quickly from the rivet holes and which serve to hold thecomplementary rivet holes in alignment. The parts thus temporarilyarticulated are then permanently joined by means of conventional rivets;and when enough of the latter have been put in place and headed up toensure the alignment of a seam, the temporary rivets are withdrawn andthe permanent riveting operation completed.

In manufacturing airplanes the rivet holes are drilled barely largerthan the shanks of the rivets to be inserted therein and, for thatreason, the rivet holes must be brought accurately into align` mentbefore the rivets can be inserted.

Because of the great number of rivets which enter into the constructionof a large metal airplane the cost of that operation is large; and,consequently, riveting speed is of utmost importance. Anything entailingunnecessary delay in getting the rivets into the holes spells reducedemciency, and it will be apparent that in avoidance of such reducedefficiency it is essential that the removable rivets be capable ofaligning and holding in accurate alignment the complementary holes whichthey occupy. The best of the removable rivets heretofore available arecapable under ordinary and favorable circumstances of accuratelyaligning the rivet holes; but it has been found that where surfaceirregularities obtain the prior art fasteners in common use will causeenough misalignment of the rivet holes seriously to impede the rivetersand thus decrease man-hour production. One of the principal objects cfmy present invention is to provide a temporary rivet which isself-compensating with respect to small irregularities in the parts tobe Joined and which, therefore, will bring the rivet holes intoalignment notwithstanding such irregularities.

Because of the unavoidable frailness of the pin parts designed to passthrough the rivet holes, the removable rivets heretofore used in greatquantities by the aircraft industry have been a source of inordinateexpense due to excessive breakage; and one of the objects toward whichthe present invention is directed is a reduction or substantialelimination of -that loss.

A further object of my invention is to devise a removable rivet having abody portion of smaller outside diameter than is feasable with similardevices of the prior art-thus greatly facilitating the heading up ofclosely spaced rivets.

Still another object is to provide a removable rivet which is moreeillcient in operation and less susceptible of breakage but at the sametime less costly to manufacture than any of the related prior artdevices.

A preferred embodiment of my invention is illustrated in theaccompanying drawing, wherein:

Fig. 1 is a longitudinal sectional view of a removable rivet in itsnormal state.

Fig. 2 is an end view of the rivet. l

Fig. 3 is a sectional view similar to Fig. 1 but showing the springsfully compressed so as to enable the pin and expander to be pushedthrough a pair of complementary rivet holes.

Fig. 4 is a sectional view similar to Figs. 1 and 2 but showing thedevice in actual operation as a temporary rivet.

Fig. 5 is a greatly enlarged cross-sectional view taken along the line5-5 of Fig. 3.

Fig. 6 is a fragmentary sectional view illustrating a modification.

Like other removable rivets of the same class, my rivet is operated mostconveniently by a plier of special construction which is well known tothose skilled in the art and which, therefore, is not here illustrated.

In Figs. 3 and 4 are shown a pair of overlapping plates I0 and Il,respectively, which have been punched or drilled for riveting, and whichit is desired to assemble, preliminarily, with rivet holes in alignment,until a few permanent rivets can be put in place and headed up.

My temporary rivet, in its preferred embodiment, comprises the followingmajor parts: a cup-shaped body member I2; a. spring adapter I3; a capI4; an expansible split pin I5, consisting of two identical parts I5aand I5b; expanding means consisting of a rod or wire I6 to one end ofwhich is attached (orlx integral with) a bead or enlargement Il; a coilspring I8; a second coil spring I9, and a plug 20.

The two identical parts lia and I5b which constitute the expansiblesplit pin are elongated spring tempered relatively thin formed sheetsteel members of crescent shape cross section (see Fig. 5) and areprovided each, at one end, with a flange 2|, 22, respectively, by whichthey are anchored to the adapter I3. Pin I5 extends throughan axialopeningv 23 in adapter I3 and through an axial opening 24 in body memberI2. i

Spring Il is interposed between body member I 2 and adapter I3 and. asshown in Fig. 1, normally` serves to. hold. the adapter away from thebody f and, consequently, to retract the free ends of the -pinmembersliaand I5b which, as will be seen, n are each bulged semi-ellipsoidally.

l' presently will be explained.

g The wire or rod I6 is'bent at one end and thereby anchored to the capIl through which it g passes; and, preferably, it is soldered or weldedtothe cap.

14 Spring I3 is interposed between adapter I3 and' cap I4 and itsultimate function is to pull the bead or enlargement Il, through themedium of wire I3, into the bulged end portion ofthe pin v so as toexpand the same. Spring I9 preferably is much stiffer than spring I3 fora reason which e i With the device in its normal state, as depicted inFig. l, the bulged portion ofthe pin is'too l i. large, diametrically,to enter a rivet hole of the 1. size in which the devicev is intendedfor use; but/ Vwhen the springs are compressed, as per Fig. 3,

the bead I'I is ejected from the bulged portion .of the pin, allowingthe latterto contract dief g metrically enough to permit its passagethrough` the rivet holes. In addition, the pin parts I5a vbreakage whichhasv heretofore been experienced in the use of .temporary rivets intheaircraft and lib, being of spring-tempered steel, will yieldfdianietrically under pressure after Ahead1-Il has been ejectedtherefrom. 'Ihe maximum diameter of bead I'l is preferablyjust slightlyless thanl i' that of the rivet holes, while the diameter "A" v .pin islarger than that of the rivet holes by an .(Fig. 4') of the 'expandedbulged portion of the@ '35 amount equal to twice` the thickness of thevsheet. Y l lmetal stock voutoi which the parts I5a and *|517` y. vareformed. 1 While not indispensable to the operativeness of my invention,it is. distinctly` preferable that;

A10i l j spring Ilbe substantially stiffer than spring IB;'1

bulge of the pin before the latter was retracted back through the'`rivet holes... v

A temporaryrivet such as herein described,

but having spring'sofequal stiffness or in which .sp1-.mgl I8 is evensomewhat stiffer than spring I3 wouldbe operative and, I believe,entirely feas able and f o'r that reason I do not wish to be understoodas disclaiming any embodiment of myjinvention in which-spring I9 is notls tiier .than spring I8.V .i i J Plug 20 may' bev either threaded intoor pressed into the adapter I3. Preferably it is insertedto such anextent as to allow of some space between the end of'the plug and theflanges ZI and 22. This permitsof a. limited angulary and unequallongitudinal axial displacement of the pin parts I5a and I5b and of thepin as a whole relative to the adapter-fall of whichls desirable asacompensating factor with respect to irregularities inthe parts to-beriveted. VIt serves to avoid or v lessen the setting up of stresseswhich it is be-- lieved have been .responsible for much of the industry.

Anotherffeature which contributes to avoidance .of lateral Astrainsresulting from irregularities in the parts to be riveted is the factthat adapterv I3 floats on springs ljand is therefore capable ofmovingangularly about its axis so as tocompensate f or high spots on the partsto be riveted 'such as would cause the longitudinal axis of body. I2.tobe deflected out of alignment with the rivet holes..

complishedis the fact-that, dueto the full .floating constructionillustrated and the symmetrical arrangement o'f pinparts andexpander;the pin. A is eiectiveto pull the rivet. holes into accurate alignmentnotwithstanding small irregularities which, cause tilting of thebodyfl2, axially. With back vinto the bulged portion of the pinbefore.

` the pin starts to retract under expansion of spring Il. Itwill-be-.observed that bead I'I isl l responsivein its movements toexpansion andv` vcontraction of` both springs I8 and I9, but that thelongitudinal movementsof pin I5 are in1 v .response only to expansionsand contractions I lof spring Il.

It will be apparent that by making spring I9v substantially stiffer thanspring I8 an advantage is gained in. that the. projecting end of pin I5. need be' only slightly longer than is necessary for it to passcompletely 'through plates I0 `and .II (see Fig. l3). lhis is' .truebecause the pin does not start to retract until after bead I1 hasjre-'entered the bulge of the pin.

@where riveting operations are conducted on a respe'ctto thev axis'oflthe .rivetholes With an. f v

ypin connected rigidly to the body any such tiltilf. 'ing is Acffrtainto cause some misalignmentof the rivet holes; and a misalignment of onepair of rivetfhole's.- in a seamwill generally cause mis- 1 alignment lof lall of'them-makin'g it difficult to insert the permanent rivets.While that might not be-v'ery important on a casual riveting job,

itis very importantV in the. Aaircraft industry huge scale andfwhereriveting speed is of paramount importance.

rivet is that the body I2 maybe of very small [diameter solasto permitit to be used where Often, in the past, it has been necessary to grindvAnother desirablefeature of my' temporary rivet holes vare very closetogether and where it is necessary to' provide a temporary fastener in arivet hole yimmediately adjacent `to one in which a` permanent rivet isto headed up.

. fiat spots on 'the bodies of temporary rivets in order to provideclearance for the riveting tool.

If, on the contrary, the two springs I Band I3 were made oi? equalstiffness, pin I5 and beadA Il e would start retracting simultaneously.The bead v would retract more rapidly than the pin because it isresponsive to the expansion .of both springs while the pin is responsivetoonly one spring;

and if the pin and wire I6 and other parts wereY made long enough thebead wouldenter the My temporary'rivet can be made oi? extremelysmallbody diameter for use in close quartersv valthough for general useI prefer to make it of a diameter somewhat larger than the minimum.

for screw machine. or die cast production;l but it will be self-evidentthat these parts, Vslightly v modified, can be made of sheet metal in. apunch press.

Part Itisv preferably a piece `of music wire,

But veven more important than the reduction of breakage which vinytemporary rivet hasac-v Parts I2, I3, and I4, as illustrated aresuitablev but I refer to it, broadly, las a rod, because it is notnecessarily wire.

The bead I1 is preferably made by swaging the wire Il and is integraltherewith. It may, however, be a separate part attached to the wire orrod. Preferably, it is approximately ellipsoidal in form.

Springs Iland Il could be replaced by rubber cushions, but probably tono advantage. However, I wish it to be understood that in referring tosprings I mean to include rubber and other resilient cushioning meanswithin the scope of that term.

For want of a better and more descriptive term I have referrdto theparts lla and lib, jointly, as a pin That term was chosen because theparts in question perform a function which is commonly performed by apin.

'I'he cap Il is merely a convenient means of interconnecting the end ofrod or wire Il with spring I 9 and in using the term cap in the appendedclaims I intend to include any means whatever for effecting such aconnection. Likewise, the adapter Il is merely a convenient means ofestablishing a suitable connection between pin I5 andthe springs and ofproviding a stop for limiting the travel of the pin and compression ofspring I8; and I mean to embrace within the scope of that term any meansadapted to accomplish either or both of those functions.

In Fig. 6 there is illustrated a modification of the previouslydescribed device, wherein the body I2 is recessed at 25 to form a pocketfor the reception of the bulged end of the pin when the latter isretracted. This construction is advantageous in that it providesprotection for the pin and bead against injury due to rough handling. Ifdesired, recess 25 can be made deep enough to permit the bulged end ofthe pin and bead I 'I to be drawn completely into the body.

What is claimed is:

1. A fastener comprising: a body, an expansible elongated pin co-axialwith said body and projectable axially therefrom, a spring connected toone end of said pin and functionally interposed between said pin andsaid body and operative to retract said pin longitudinally, a secondspring in series with said rst spring, a rod connected to said secondspring at a point remote from said first spring, said rod extendingaxially through said pin and having an enlargement at its free endportion, said enlargment being operative to engage the free end portionof said pin and effect expansion thereof, said enlargement normallyengaging said pin to effect diametrical expansion thereof but movableaxially to permit diametrical contraction of said pin in response tocompression of said second-mentioned spring.

2. A fastener comprising: a body, an expansible, elongated split pinco-axial with said body and having a free end portion projectableaxially therefrom, said free end portion being bulged, a spring withinsaid body and interposed functionally between said body and said pin,that end of said pin which is remote from said free end being connectedto said spring, a second spring in series with said ilrstspring andsituated adjacent that end of said first spring to which said pin isconnected, a rod connected to said second spring at a point remote fromsaid first spring, said rod extending axially through said pin, andexpanding means carried by said rod and operative upon the bulgedportion of said pin to eilect diametrical expansion thereof, saidexpanding means being movable out of operative engagement with said pinin response to compression of said second-mentioned spring.

3.*A fastener comprising: a body, an expansible, elongated split pinco-axial with said body and having a free end portion projectableaxially therefrom, said free end portion beingv bulged diametrically, abead operative to occupythe interior of the bulged portion of said pinso as to effect diametrical expansion thereof, said bead being ejectablefrom said bulged portion to permit contraction thereof, and yieldablemeans normally holding said bead within the bulged portion of said pin.

4. A fastener comprising: a body. an expansible, elongated split pinco-axial with said body and having a free end portion projectableaxially therefrom, said free end portion being bulged diametrically, abead operative to occupy the interior of the bulged portion of said pinso as to effect diametrical expansion thereof, a spring within said bodyand connected to that end of said pin which is remote from said bulgedportion, said pin being movable axially in response to compression andexpansion of said spring, a second spring in series with said rst springand disposed adjacent to that end of said first spring which is remotefrom the bulged portion of said pin, and a rod connected to said beadand extending axially through said pin and said springs, said rod beingconnected to said second spring at a point remote from said irst spring,said rod being operative in response to compression of said secondspring to move said bead out of the bulged portion of said pin, saidsecond spring being operative, when released, to retract said bead intosaid bulged portion.

5. A fastener comprising: a body and a cap and an adapter interposedbetween said body and cap, an expansible pin anchored at one end to saidadapter and extending through said body, expanding means for said pinincluding a bead and a rod attached at one end to said bead, said rodextending longitudinally through said pin, body and adapter andconnected to said cap at the end of said rod remote from said bead, arelatively soft spring interposed between said adapter and said body anda relatively stiff spring interposed between said adapter and cap, saidbead normally being held by said relatively stiff spring in engagementwith said pin so as to expand the end portion thereof, said bead beingmovable away :from said pin in response to compression of saidrelatively stiff spring `whereby to permit said pin to contractdiametrically.

6. A fastener comprising: a body, an adapter v and a cap in axialalignment, said adapter being interposed between said body and cap, adiametrically expansible split pin anchored at one end to said adapterand extending through said body, expanding means for said pin includinga rod attached at one end to said cap and extending axially through saidadapter, body and pin, said rod having an enlargement at the end thereofremote from said cap, said enlargement being normally in actuatingengagement with the free end portion of said pin for expanding the same,a relatively soft spring interposed between said body and said adapterand a relatively stiff spring interposed between said plunger and saidcap.

7. A fastener comprising: a body, an adapter and a cap in axialalignment, said adapter being interposed between said body and cap, adiametrically expansible split pin loosely anchored at one end to saidadapter, said pin being capable of limited angular axial displacementwith respect to the axis of said adapterand body, expanding means forsaid pin including a rod attached at one end to said cap and extendingaxially through said adapter, body and pin, said rod having anenlargement at the end thereof remote from said cap, said enlargementbeing normallyv in actuating engagement with the free end portion ofsaid pin for expanding the same, a relatively soft spring interposedbetween said body and said adapter, and a relatively stift springinterposed between said adapter and said cap.

, 8. A removable rivet comprising: a body, a diametrically expansiblepin consisting oi a plurality of elongated members disposed substan'tially symmetrically about a common longitudinal axis, said pin beingmovable longitu dinally relatively to said body, one end portion of saidpin being bulged, a bead situated adjacent the bulged end portion ofsaid pin and capable of entering said bulged portion for ex-l pandingthe same, a spring for retracting said pin into said body, said springbeing responsive to a compressive force to permit' the bulged endportion of said pin to be projected away from said body,A a secondspring, stiier than saidl rst-mentioned spring and in series therewith,said second spring being situated at that endl of said mst-mentionedspring which is most remote from said bulged portion, a rodextendingaxially through said pin and springs, said rod being connected at oneend to said bead and Y at the other end to said second spring, saidsprings being normally operative to hold said pin and bead in theirretracted positions.

9. A removable rivet comprising: a .cupshaped body member having anaxial opening, a coil spring seated'within said member and co-` axialtherewith, a secondA coil spring substantially stiier than saidmst-mentioned spring and situated in series therewith, said springshaving a common axis. an adapter interposed between said springs -andco-operative with' said body member to limit the deection of saidrstmentioned spring under compression, a diametrically expansible pinconsisting of a plurality of elongated parts disposed substantiallysymmetrically about the axis of said body member andvextendinglongitudinally through said axial opening, said pin being looselyanchored at one end to said adapter and having a bulged portion atitsother end, an expander bead normally situated within said bulgedportion but movable therefrom along said axis, and a rod connected tosaid bead and extending axially through said pin, body and springs, saidrod being connected to said second-mentioned springs at a point remotefrom said rst-mentioned spring.

f RUSSELL W. EDWARDS. y

